2013 was a great year for Miley Cyrus, with two No. 1 hits and enough media attention to last a lifetime, but the pop singer isn’t showing any signs of slowing down, with a new “MTV Unplugged” special scheduled to air on Wednesday night. And if that wasn’t enough to get music fans excited, E! Online is now reporting that Cyrus will be joined by none other than Madonna as a surprise guest performer. At least, it was supposed to be a surprise.

No word yet on what song the two will be performing, but they were spotted rehearsing together ahead of the special’s Tuesday taping. Madonna has a long history of collaborating with fellow artists, teaming up with Macklemore & Ryan Lewis to perform “Same Love” at the Grammys on Sunday night, as well as her much-publicized performance with Britney Spears and Christina Aguilera at the MTV Video Music Awards in 2003.

Cyrus’ headline-grabbing duet with Robin Thicke at last year’s VMAs drew a lot of comparisons to that famous 2003 performance, so it makes sense that the two women would be comfortable working together.

MTV recently released a press release for the special, stating:

“The performance will showcase a more intimate side of Cyrus and feature surprise guests for an unexpected re-invention of the songs that have defined her career, including several from her No. 1 critically acclaimed album, Bangerz. Miley and her fans have always had an intimate and direct connection through her music, personality and no-holds-barred attitude and the Unplugged stage will serve as the perfect platform for her to show viewers what inspires and ignites her music and her passions.”

What’s most interesting about the press release is the mention of multiple surprise guests, because Madonna is the only one that’s been revealed so far. It doesn’t seem likely that any more will be ruined before Wednesday night, so you’ll just have to tune in to find out what else Cyrus and MTV have in store.